浸水程度对煤自燃特性影响研究

煤矿开采过程中，地下水流入煤层裂缝，煤体受到不同程度水量浸泡，其自燃特性受到影响不利于矿井防灭火工作。为研究不同浸水程度煤体自然特性，对唐山矿0250煤层煤样进行水浸煤制作，对不同浸水程度煤样进行程序升温、低温液氮吸附、傅里叶红外光谱实验。得出实验结果：随着浸水程度的提高，比表面积下降，大孔比例增加，耗氧速率和CO、CO2产生率提高；脂肪烃基团含量降低，芳香烃和含氧官能团含量增大。实验结果表明：浸水导致煤体小孔向大孔转化，孔隙与裂隙的连接性增强，导致煤体与氧气接触面积增大，有利于对氧气的物理吸附；浸水促进过氧络合物的生成，有利于对氧气的化学吸附；随着浸水量的增加，羟基（-OH）含量提高，煤体在低温氧化阶段表现出氧化特性越明显，羰基（C=O）、羧基（-COOH）含量增加，导致煤体氧化燃烧阶段氧气消耗量、耗氧速率及CO、CO2产生率提高；浸水促进了煤体内官能团的相互转化。

Study on the influence of water immersion degree on spontaneous combustion characteristics of coal

In the process of coal mining, groundwater flows into the crack of coal seam and the coal body is soaked by different degrees of water. In order to study the natural characteristics of coal with different degrees of water immersion, the coal samples of 0250 coal seam in Tangshan Mine were made by water immersion, and the coal samples with different degrees of water immersion were tested by temperature-programmed, low-temperature liquid nitrogen adsorption and Fourier infrared spectroscopy. The experimental results show that with the increase of immersion degree, the specific surface area decreases, the proportion of macropores increases, oxygen consumption rate and CO, CO2 production rate increase; The contents of aliphatic hydrocarbon groups decreased while the contents of aromatic hydrocarbons and oxygen-containing functional groups increased. The experimental results show that water immersion leads to the transformation of small pores into large pores, and the connection between pores and cracks is enhanced, which leads to the increase of the contact area between coal and oxygen, which is conducive to the physical adsorption of oxygen. Soaking promotes the formation of peroxide complex, which is beneficial to the chemical adsorption of oxygen. With the increase of leaching water, the content of hydroxyl (-OH) increases, and the oxidation characteristics of coal are more obvious in low temperature oxidation stage, and the content of carbonyl (C=O) and carboxyl (-COOH) increases, leading to the increase of oxygen consumption, oxygen consumption rate and CO and CO2 production rate in coal oxidation combustion stage. Soaking promotes the mutual transformation of functional groups in coal.